[2.1.20] Entity with input-output fluid boxes improperly constraining temperature

[mystify]

I have a modded entity that produces steam into a fluid box with an input-ouput flow direction and a output production type. The filter is set to "steam" with no minimum or maximum temperature set.
This results in a steam pipe that cannot connet to a steam engine, because the steam engine has a min temperature of 100 and no max temperature, and my fluid box has a max and minimum temperature of 100.

this worked fine in 2.0, and I can connect a boiler to the output pipe (it shows no max or min temperature)

I've attached a minimal mod and save file to demonstrate. Just try placing a pipe between the two buildings.

the minumum and maximum temperature seems to be set by the temperature from the crafting recipe.